Diffuse x-ray scattering study of lead magnesium niobate single crystals

被引：112

作者：

You, H ^{[1
]}

Zhang, QM ^{[1
]}

机构：

[1] PENN STATE UNIV,MAT RES LAB,UNIVERSITY PK,PA 16802

来源：

PHYSICAL REVIEW LETTERS | 1997年 / 79卷 / 20期

关键词：

D O I：

10.1103/PhysRevLett.79.3950

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Single crystals of lead magnesium niobate, PbMg1/3Nb2/3O3, were studied with x-ray scattering measurements at temperatures between 10 and 350 K. The diffuse scattering around odd-integer Bragg reflections (H + K + L = odd) has a significant anisotropic component with ledges along (110) directions. We show that the transverse optic (ferro distortion) modes whose polarizations are along (110) directions are soft and responsible for the observed diffuse scattering. Upon cooling, these modes undergo a freezing process with q-dependent freezing temperatures. Below the lowest freezing temperature (T less than or similar to 190 K) the diffuse scattering follows 1/q(2) law, indicating an elastically distorted, static structure.

引用

页码：3950 / 3953

页数：4

共 22 条

[1]

Ashcroft N.W., 1976, Solid state physics Holt, Rinehart and Winston, Vfirst

[2] CALCULATIONS OF DIELECTRIC-PROPERTIES FROM THE SUPERPARAELECTRIC MODEL OF RELAXORS [J].